Apparatus for incinerating material



Nov. 12, 1935. R. GRANGER APPARATUS FOR INCINERATING MATERIAL Filed Dec. 6, 1934 R O T N E V m Foyer Granger BY M ATTORNEYS l Patented Nov. 12, 1935 UNITED STATES PATENT OFFICE APPARATUS FOR- INCINERATING MAT ERIAL 3 Claims.

This invention relates to apparatus for incinerating material, such as sewage.

More specifically state-d, the invention relates to apparatus for disposing of sewage screenings and sludge cake. The disposal of such matter constitutes a very serious problem in large cities and involves an enormous expense. Sometimes such material is towed out to sea and dumped,

hus polluting the coastal waters. It has been proposed to convert the material into fertilizer, but this has been found to be too expensive to be practical.

The burning of sewage screenings and sludge cake presents unusual problems due to the relatively large water content even after a part of the water has been removed by vacuum filters and other means. Unless the temperatures in the various parts of the apparatus are properly regulated and controlled the outer layer of the material will be closed or sealed with the moisture confined therein. Furthermore, it has been found that for proper and efiicient incineration the temperature at the receiving end of the apparatus should be relatively low and the material should be gradually fed through the apparatus and kept in motion, being subjected to increasing temperatures until it is burned to ash.

This invention has for one of its objects to provide apparatus for so burning or incinerating sewage screenings or like material that the final product will be in the form of ash easily disposed of and no objectionable gases will be released to the atmosphere.

Another object of the invention is to provide apparatus of the character described and for the purpose described, so designed that the material being incinerated will be kept in motion during its passage through the apparatus so that the heat and hot gases will contact all parts thereof.

Another object of the invention is to provide apparatus of the character described so constructed and arranged that the temperatures at the various parts of the apparatus will be regulatedand controlled.

Further objects of the invention will appear from the following specification taken in connection with the drawing which forms a part of this application and in which Fig. l is a sectional elevation somewhat diagrammatic of apparatus constructed in accordance with the invention;

Fig. 2 is a transverse sectional elevation through one of the rotating drums; and

Fig. 3 is a transverse sectional elevation through the other rotating drum showing the mechanism for rotating the drum.

The invention briefly described consists of a method of incinerating sewage screenings, sludge cake or like material by subjecting the material to gradually increasing temperatures while maintaining the material in motion during its passage through the apparatus so that the hot gases will engage and contact with all parts of the material and the material will be broken up and burned and the gases will be released therefrom. The apparatus for carrying out the method consists of a pair of rotary drums oppositely inclined and so arranged that the material will pass first through one drum and then through the other and at the outlet end of the second drum will be reduced to ash. The temperatures are so regulated throughout the apparatus that the temperature at the receiving end of the first drum will be relatively low, such for instance as about 200 F., but will be gradually increased as the material passes through the apparatus, the temperature at the outlet end of the second drum being relatively high, such as 2000 F. The drums are continually rotated at a relatively slow rate of speed and are provided with lifts or baffles 20 so that the material will be carried from the bottom to the top of the drum where it will drop again and during this operation the hot gases will engage the particles of material.

Further details of the invention will appear from the following description.

In the particular embodiment of the invention illustrated in the drawing the apparatus comprises a pair of drums A and B which are supported at the ends on suitable rollers ID. The upper drum is supported on a frame work I I and the lower drum on frames 12 mounted in a furnace or incinerator. An oil burner nozzle l3 of any suitable construction directs a flame into the outlet end of the drum B and this end of the drum empties into an ash pit I4. The drum 3 is provided with a lining E5 of fire-brick or other suitable heat resisting material and the inner surface of the lining has projecting inwardly therefrom a plurality of radially disposed bafiles or lifts H5. The drum is rotated by a motor it which drives a motor shaft ll connected by a bevel gear connection It to a shaft It on which a driving roller 2i! is mounted.

The drum A is not subjected to as high temperatures as the drum B and therefore has no lining, but is provided with inwardly extending, radially disposed lifts 2| which extend longitudinally of the drum and are similar in construction. to the lifts It. The drum A is driven from a motor 22 by driving connections similar to those shown in Fig. 3 for the drum B. The left hand ends of the two drums viewing Fig. 1 open into a chamber 33 which has projecting upwardly thereinto an inclined shelf 3| which receives the material discharged from the discharge end of the drum A and directs this material into the receiving or inlet end of the drum B.

The maintenance of proper temperatures of different parts of the apparatus is very important to a gas washer 51.

and in order to regulate the temperatures an opening 32 leads into the chamber 3!] and is provided with adjustable louvers 33. These louvers are provided with a thermostatic regulating device 34 so that they will automatically open when the temperature exceeds a predetermined maximum and will automatically close when the temperature falls below this predetermined maximum.

The sewage screenings are collected in a tank or drum T and are pumped from this drum by a pump R to a. hopper H. The hopper discharges into a casing 35 in which is mounted an endless belt 33 which is supported on hexagonal drums or pulleys 31. The shaft of pulley 3'! has mounted thereon a gear 24 meshing with a gear 25 driven by a gear 26. The shaft of gear 26 has mounted thereon a pulley 21 driven by a belt 28 from a motor M. The belt 36 on its upper lap passes between upper and lower sets of presser rolls 38 and 39 which squeeze the material and remove a considerable part of the water therefrom. The

water drops into a tray 40 and is drained therefrom through a pipe 4!. The discharge end of the belt 36 discharges the pressed screenings into a chute 42 which leads to a conduit 43 having a screw conveyor 44 mounted therein. The discharge end of the conduit 43 is located in the receiving end of the drum A. The chute 42 has also connected thereto an upwardly extending receiving conduit 45 into which sludge cake or like material may be introduced.

The screw conveyor 44 may be driven in any suitable manner and in Fig. l is shown as driven by a sprocket and chain connection 46, 41 and 48 on a shaft 49. This shaft is driven by a gear connection 50, 5| from the motor shaft 52 which in turn is driven by a motor 53.

The chamber 30 at the left hand ends of the drums'A and B communicates with a stack S. A considerable amount of the gas freed from the incinerated material passes directly from the chamber 30 to the stack S. A certain portion of the gas, however, passes upwardly and through the drum A, being utilized to heat the material passing through the drum. A chamber 55 at the receiving end of the drum A communicates with an outlet conduit 56 which in turn is connected From this washer the gas passes through a conduit 58 which is connected at its lower end to the receiving end of an exhaust fan P, the discharge end of this fan communicating with a conduit 59 which discharges into the chamber 30.

Operation 1 the receiving end ofthe drum A by the spiral conveyor 44 and gradually passes from the receiving end to the discharge end of this drum. During this passage the material is continually carried upwardly by the lifts and drops to the bottom of the drum and the hot gases which are passing through the drum in the opposite direction engage the moving particles. The temperature at the receiving end of the drum A is approximately 200 F., although this may be varied as conditions require. At the discharge end of the drum A the temperature may be approximately 800 F. and thus it will be evident that the material in passing through thisdrum has been gradually raisedin temperature. The material discharged from the drum A drops to the shelf 3| and enters the drum B and is gradually fed from the left hand to the right hand end thereof viewing Fig. 1. During this passage of the material it is still kept in mo- 5 tion and subjected to the increasingly hot gases 7 and high temperatures. The temperatures and rates of rotation of the drums are so regulated that when the material reaches the discharge end of the drum B it has been reduced to ash and drops into the pit I 4. The hot gases which do not pass directly from the chamber 30 to the stack S are conducted through the drum A and thence through the washer to the conduit 58 and through the fan into the stack.

Although one specific embodiment of the invention has been particularly shownand described it will be understood that the invention is capable of modification and that'changes in the construction and in the arrangement of the various cooperating parts may be made Without departing from the spirit or scope of the invention, as expressed in the following claims.

What I claim is:

1. Apparatus of the character described, comof the upper drum with the inlet end of the lower a drum, a stack communicating with said chamber, a shelf in said chamber at the inlet end of the lower drum, said shelf being inclined to direct the material into the lower drum, heating means at the outlet end of the lower drum, means inter- 5 mediate the drums for regulating the temperature in the chamber and upper drum, and means for removing gas from the inlet end of the upper drum. i

2. Apparatus of the character described, comprising a pair of rotatable drums disposed one above the other, means for rotating said drums, inwardly extending longitudinal vanes or lifts in each drum, a chamber connecting the outlet end of the upper drum with the inlet end of the lower drum, a stack communicating with said chamber, a shelf in said chamber at the inlet end of the lower drum, said shelf being inclined to direct the material into the lower drum, heating means 7 at the outlet end of the lower drum, means intermediate the drums for regulating the temperature in the chamber and upper drum, and means for conducting gas from the receiving end of the upper drum to the chamber.

3. Apparatus of the character described, comprising a pair of rotatable drums disposed one above the other, means for rotating said drums, inwardly extending longitudinal vanes or lifts in each drum, a chamber connecting the outlet end drum, a stack communicating with said chamber,

a shelf in said chamber at the inlet end of the lower drum, said shelf being inclinedto direct the material into the lower drum, heating means at the outlet end of the lower drum, means intermediate the drums for regulating the temperature in the chamber and upper drum,a gas washer, means for conducting gas from the inlet end of the upper drum to said washer, and means for conducting the gas from the washer to said chamber and thence to the stack. 7

' ROGER. GRANGER.

of the upper drum with the'inlet end of the lower 60 

